build: Fix build with Python 3.6-3.9
build: Fix build with Python 3.6-3.9

Doing string replacements on binary data requires the regexs, search
strings, and the replacements to be binary strings.  This was only an
issue in the relatively-new TS defs generator.

This fixes all of those string manipulations to be binary-string
manipulations.

Closes #3003

Change-Id: If30df6d34b4626896d831768397359dd26e04ca1

tvoli/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player